1. Field of the Invention
The present invention relates to an apparatus for arranging a number of objects into an array and supplying the objects arranged in the array, and particularly to the art of improving reliability with which the apparatus supplies the objects.
2. Related Art Statement
Japanese Patent Application Laid open for inspection under Publication No. 8(1996)-48419 discloses an example of the above-indicated apparatus. This apparatus includes a hopper, a chute, and a discharging-promoting tube. The hopper stores a number of objects in bulk, i.e., in such a manner that each object takes an arbitrary posture. An initial-end portion of the chute is connected to an outlet of the hopper. The discharging-promoting tube is provided in the vicinity of the initial-end portion of the chute, such that the tube is vertically movable relative to the chute. The tube has an inner passage which provides a portion of the initial-end portion of the chute. The vertical movement of the tube moves objects which clog the outlet of the hopper, and/or objects which engage each other and prevent each other from entering the chute, that is, make a xe2x80x9cbridgexe2x80x9d over the chute. Thus, the tube eliminates the clogging and/or the bridge, thereby promoting discharging of the objects into the chute.
However, though the discharging-promoting tube is vertically moved, objects may not enter the tube with high reliability and the apparatus may fail to supply the objects.
The present invention provides an arranging and supplying apparatus which has one or more of the technical features that are described below in respective paragraphs give parenthesized sequential numbers (1) to (20). Any technical feature which includes another technical feature shall do so by referring, at the beginning, to the parenthesized sequential number given to the latter feature. Thus, two or more of the following technical features may be combined, if appropriate. Each technical feature may be accompanied by a supplemental explanation, as needed. However, the following technical features and the appropriate combinations thereof are just examples to which the present invention is by no means limited. In addition, in the case where one technical feature recites a plurality of items, it is not essentially required that all those items be simultaneously employed. That is, it is possible that only a portion (one, two, . . . , but not all) of those items be selected and employed.
(1) According to a first feature of the present invention, there is provided an apparatus for arranging and supplying a plurality of objects, the apparatus comprising a hopper which stores the objects in bulk and which has a funnelform bottom surface at least a portion of which extends in a reference direction inclined with respect to a horizontal plane; a chute which includes an end portion extending, from a lowest portion of the hopper, substantially parallel to the reference direction, and which causes the objects arrange din an array to be moved; a discharging-promoting member which is provided in a vicinity of the end portion of the chute, which is movable substantially parallel to the reference direction, and which promotes discharging of the objects from the hopper to the chute while arranging the objects into the array; and a drive device which reciprocates, relative to the chute, the discharging-promoting member between an advanced position where an end portion of the discharging-promoting member projects into the hopper and a retracted position away from the advanced position. The entirety of the bottom surface of the hopper may be inclined relative to the horizontal plane. Otherwise, at least a portion of the other portion of the bottom surface than the inclined portion thereof may be vertical. That is, the bottom surface of the hopper may be a semi-funnelform one. The objects may be any articles, for example, electric components according to the twentieth feature (20) described later. Each of the objects may be any transverse cross section, such as a polygonal (e.g., quadrangular or triangular) transverse cross section, or a circular transverse cross section. The transverse cross section of the chute may be identical with, or different from, that of each object. The discharging-promoting member being positioned at the retracted position thereof may be completely retracted into the chute, or otherwise, may be partly remaining in the hopper so long as the amount of projection of the promoting member into the hopper is smaller when being positioned at the retracted position than when being positioned at the advanced position. The discharging-promoting member may be a member which provides, according to the fourth feature (4) described later, a portion of the hopper-side end portion of the chute that defines an object-supply passage therein, or a member which does not provide any portion of the hopper-side end portion of the chute and is provided at a location around the end portion and which is reciprocated between the advanced and retracted positions. The object stored in the hopper are moved toward the chute by the inclined portion of the bottom surface of the hopper. When the discharging-promoting member is moved to the advanced position, the objects present in the lowest portion of the hopper are moved and prevented from clogging the opening of the chute in the bottom surface or making a xe2x80x9cbridgexe2x80x9d over the opening. Thus, the discharging-promoting member promotes or helps the objects to enter the chute. Since the end portion of the chute extends substantially parallel to the reference direction in which the inclined portion of the bottom surface extends, the objects riding on the inclined portion slide and move toward the chute owing to the inclination of the inclined portion, and only the object whose transverse-cross-section phase is equal to that of the opening of the chute can directly enter the chute. Since the objects are guided toward the chute by the continuous inclined portion of the bottom surface of the hopper, the object can more easily enter the chute. Thus, the present arranging and supplying apparatus can more reliably or stably supply the objects. When the discharging-promoting member is moved to the retracted position, the objects present around that member are moved toward the chute to follow that member, and only the object whose transverse-cross-section phase is equal to that of the opening of the chute can enter the chute. According to the first feature (1), the end portion of the chute extends substantially parallel to the reference direction in which the inclined portion of the bottom surface extends, and the discharging-promoting member is movable substantially parallel to the reference direction. Therefore, the present arranging and supplying apparatus can reliably and stably supply the objects, without needing a complicated construction. In addition, since the end portion of the chute extends from the lowest portion of the hopper and each object moves from the lowest portion into the end portion, every object stored in the hopper can enter the chute. Thus, the present apparatus can supply all the objects to the last one.
(2) According to a second feature of the present invention that includes the first feature (1), the end portion of the chute has an opening which opens in the bottom surface of the hopper, and the discharging-promoting member and the portion of the bottom surface of the hopper are located on both sides of the opening of the chute, respectively. The discharging-promoting member is, preferably, a flat member according to the third feature (3), or a grooved member according to the fifth feature (5)), but is not limited to those members. That is, the discharging-promoting member may be provided by a different member having a different shape, such as a bar-like member. In addition, the discharging-promoting member may provide at least a portion of the end portion of the chute that is connected to the bottom surface of the hopper, or may be provided separately from the chute, e.g., at a position above the chute. In the present arranging and supplying apparatus, the discharging-promoting member moves the objects which ride on the objects which directly ride on the inclined portion of the bottom surface of the hopper, and the movement of the former objects causes the latter objects to move toward the chute, thereby promoting discharging of the latter objects into the chute. In the case where the discharging-promoting member is provided by a flat member or a bar member, a wide space continuous with the opening of the chute is left between that member and the inclined portion of the bottom surface of the hopper, when that member is advanced to the advanced position, so that the objects moved by the advancing of the member can easily move toward the chute.
(3) According to a third feature of the present invention that includes the first or second feature (1) or (2), the discharging-promoting member comprises a flat member which has an elongate cross section taken along a plane perpendicular to the reference direction. According to the third feature (3), the cross section of the flat member as the discharging-promoting member is considerably small and accordingly the flat member contacts a considerably small area of each object. Therefore, the drive device can reciprocate the flat member with a considerably small drive force.
(4) According to a fourth feature of the present invention that includes the third feature (3), the end portion of the chute has an object-supply passage in which the objects are moved, and the flat member extends parallel to a vertical plane and has a lower surface which is parallel to a horizontal direction and which provides a portion of the end portion of the chute and thereby partly defines the object-supply passage. Accordingly to the fourth feature (4), the portion of the end portion of the chute that is provided by the flat member is reciprocated by the drive device, and accordingly the objects present around the opening of the chute in the bottom surface of the hopper are directly moved by the flat member. Thus, the present apparatus can effectively promote discharging of the objects into the chute.
(5) According to a fifth feature of the present invention that includes any one of the first to fourth features (1) to (4), the end portion of the chute has an object-supply passage in which the objects are moved and which has a quadrangular transverse cross section, and the discharging-promoting member comprises a grooved member which has a groove opening in a side surface thereof on a side of the portion of the bottom surface of the hopper. In the case where each object has a quadrangular transverse cross section, the end portion of the chute preferably has a corresponding quadrangular cross section. However, the end portion of the chute may have a different transverse cross section, such as a circular or semicircular one. According to the fifth feature (5), three of four wall surfaces defining the object-supply passage of the end portion of the chute may be provided by the grooved member as the discharging-promoting member. In the last case, when the grooved member is positioned at the advanced position, the opening of the groove of the grooved member is closed by the inclined portion of the bottom surface of the hopper, so that a passage having a quadrangular cross section is extended from the object-supply passage. This can be construed such that the chute is extended into the hopper. When the grooved member is advanced to the advanced position, the objects riding on the inclined portion of the bottom surface of the hopper are moved so that only the object whose transverse-cross-section phase coincides with that of the opening of the chute enters the chute through the extended passage defined by the grooved member and the inclined portion of the bottom surface of the hopper. When the grooved member is retracted to the retracted position, the objects are moved to follow the grooved member so that only the object that can enter the chute enters the chute.
(6) According to a sixth feature of the present invention that includes the fifth feature (5), the end portion of the grooved member has an end surface which is inclined such that as the end surface approaches a center of the object-supply passage, the end surface extends in a downstream direction of the object-supply passage. The objects are guided toward the chute by the inclination of the end surface of the grooved member. Thus, the present apparatus can reliably and stably promote the discharging of the objects into the chute.
(7) According to a seventh feature of the present invention that includes any one of the first to sixth features (1) to (6), the end portion of the chute has an object-supply passage in which the objects are moved and which has a quadrangular transverse cross-section, and the discharging-promoting member provides a portion of the end portion of the chute such that the discharging-promoting member cooperates with the chute to provide four wall surfaces which define the object-supply passage, and the discharging-promoting member is fitted in the chute such that irrespective of which position the discharging-promoting member takes relative to the chute, each of the four wall surfaces maintains continuity in the reference direction. When the discharging-promoting member is moved to the advanced position, a space extending in the reference direction is produced in rear of the promoting member. However, according to the seventh feature (7), that space can be one which does not allow each object to enter itself. Since the promoting member is fitted in the chute such that irrespective of which position the promoting member may take relative to the chute, each of the four wall surfaces maintains continuity in the reference direction, no space is produced between the promoting member and the chute in the reference direction. In addition, respective portions of the promoting member and the end portion of the chute that are fit in each other may have respective widths smaller than that of the entire wall surface defined by the fitted portions, and may be smaller than a corresponding dimension of each object. In this case, each object cannot enter the space produced between the promoting member and the chute. Thus, each object can be smoothly moved forward. The promoting member may be fitted in the hopper-side end portion of the chute such that when the promoting member is positioned at the advanced position, a rear portion of the promoting member overlaps a front portion of the end portion of the chute, or no overlapping portions of the two elements is left.
(8) According to an eighth feature of the present invention that includes any one of the first to seventh features (1) to (7), the end portion of the chute has an object-supply passage in which the objects are moved and which has a quadrangular transverse cross section, and the portion of the bottom surface of the hopper comprises an inclined bottom surface which is defined by a set of straight lines perpendicular to the reference direction, whose width in a widthwise direction perpendicular to the reference direction decreases as the inclined bottom surface approaches the end portion of the chute, and whose width is equal to a width of the object-supply passage at a position when the inclined bottom surface is connected to the end portion of the chute, and the bottom surface of the hopper further comprises two side-edge-defining surfaces which define opposite side edges of the inclined bottom surface, respectively. The inclined bottom surface may be a plane surface, or a curved surface. In the latter case, the angle of inclination of the curved surface with respect to the horizontal plane may increase as the surface approaches the opening of the chute. The two side-edge-defining surfaces may be inclined (either plane or curved) surfaces which cooperate with the inclined bottom surface to provide the bottom surface of the hopper, or vertical surfaces which vertically extend upward from the opposite side edges of the inclined bottom surface, respectively. In either case, the two side-edge-defining surfaces can guide the objects sliding on the inclined bottom surface and moving toward the chute, so that the objects reach the opening of the object-supply passage in the bottom surface of the hopper. Since the transverse cross section of the object-supply passage is quadrangular, at least a chute-side end portion of the hopper is defined by four surfaces including the inclined bottom surface and the two side-edge-defining surfaces. The last one surface may be either a vertical surface or an inclined (plane or curved) surface. In the last case, the inclined surface provides a portion of the bottom surface of the hopper, that is, another inclined bottom surface different from the above-indicated inclined bottom surface.
(9) According to a ninth feature of the present invention that includes any one of the first to eighth features (1) to (8), the drive device comprises a cam follower which is provided on the discharging-promoting member such that the cam follower is movable with the discharging-promoting member, and a pivotable cam which is pivotable about an axis line perpendicular to the reference direction and which engages the cam follower and converts an own pivotal motion into a linear motion of the cam follower. Since the drive device is provided by a cam follower and a pivotable cam, the amount, timing, frequency, etc. of movement of the discharging-promoting member can be easily defined by the shape of the pivotable cam, so that the promoting member promotes the discharging of the objects into the chute. As will be described later in DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS, the present arranging and supplying apparatus may be employed by an electric-component (xe2x80x9cECxe2x80x9d) feeder. In this case, the pivotable cam of the drive device may be pivoted by a drive device of an EC mounting machine, in synchronism with a timing at which an EC is taken out from the EC feeder by an EC-suck head of the EC mounting machine. Thus, the promoting member is moved timely, quickly, and with minimum impact.
(10) According to a tenth feature of the present invention that includes the ninth feature (9), the cam follower comprises an engage pin which projects from the discharging-promoting member such that the engage pin extends in a direction perpendicular to the reference direction, and the pivotable cam comprises a cam lever which includes a recessed portion which engages the engage pin.
(11) According to an eleventh feature of the present invention that includes the ninth or tenth feature (9) or (10), the drive device comprises a driven member which is driven by a drive member which is driven by a drive source which is provided outside the apparatus. Since the drive member is provided outside the present arranging and supplying apparatus, the present apparatus need not employ the drive source to mechanically drive the driven member, nor any electric wiring for the drive source, which contributes to simplifying the construction of the present apparatus. In addition, the outside drive source and drive member can be used commonly with a plurality of arranging and supplying apparatuses, while one arranging and supplying apparatus is replaced with another. Moreover, in the case where a plurality of arranging and supplying apparatuses are simultaneously used, a plurality of outside drive members may be employed for driving the respective driven members of those apparatuses, or a single outside drive member may be employed for driving each of the respective driven members of those apparatuses. For example, in the case where the present arranging and supplying apparatus is employed in an EC feeder which supplies ECs to an EC mounting apparatus, a plurality of EC feeders are attached to a movable table, and respective EC-supply portions of the EC feeders are sequentially moved to an EC-supply position by the movement of the table, the outside drive member may be provided at the EC-supply position, and may be commonly used with the respective arranging and supplying apparatuses of the EC feeders. In this case, the cost can be significantly reduced. In addition, the outside drive device may be used with not only the present arranging and supplying apparatus but also a different apparatus. In the last case, the cost can be further reduced. The eleventh feature (11) can be employed by the arranging and supplying apparatus according to the first feature (1). That is, the outside drive device may be one which does not include a cam or a cam follower. Likewise, the motion converting device employed by the arranging and supplying apparatus according to the twelfth feature (12) may be one which does not include a cam or a cam follower.
(12) According to a twelfth feature of the present invention that includes the eleventh feature (11), the driven member comprises a reciprocateable member, and the drive device comprises a motion converting device which converts a single reciprocative movement of the reciprocateable member into a plurality of reciprocative movements of the discharging-promoting member. Since a single reciprocative movement of the reciprocateable member is converted into a plurality of reciprocative movements of the discharging-promoting member, the objects stored in the hopper are moved more frequently and are more effectively prevented from making a bridge. In addition, the respective postures and/or phases of the objects are more frequently changed, and the objects enjoy more chances to enter the chute. Thus, the objects can be supplied with higher reliability.
(13) According to a thirteenth feature of the present invention that includes the ninth or tenth feature (9) or (10), the arranging and supplying apparatus further comprises a drive source which drives the pivotable cam. In the case where a drive source is provided outside the present arranging and supplying apparatus and, in particular, a drive source of an external apparatus is used as the outside drive source of the present apparatus, the timing and/or frequency at which the drive member is driven by the outside drive source are limited depending upon the operation of the external apparatus. In contrast, according to the thirteenth feature (13), the arranging and supplying apparatus includes a drive source and accordingly the drive source can be used to operate the move device and thereby drive the driven member at an arbitrary timing and at an arbitrary frequency. Thus, the objects can enter the chute with higher reliability. For example, in place of, or in addition to, a reciprocation of the discharging-promoting member at a timing at which an object is supplied, the promoting member may be reciprocated at least one time at at least one timing while the external apparatus waits for the supplying of the next object, so that another or other objects may enter the chute.
(14) According to a fourteenth feature of the present invention that includes the thirteenth feature (13), the drive source comprises an electric motor. The electric motor is preferably an electric rotary motor. In the case where the rotary motor is a servomotor or a stepper motor that is controllable with respect to its rotation angle or amount and its rotation direction, the operation of the pivotable cam can be easily controlled.
(15) According to a fifteenth feature of the present invention that includes the thirteenth or fourteenth feature (13) or (14), the drive device comprises a driving control device which operates, while the apparatus supplies each one object, the drive source by an amount which causes a plurality of reciprocative movements of the discharging-promoting member. For example, in the case where the pivotable cam is an eccentric cam and, when the eccentric cam is rotated by 360 degrees, the discharging-promoting member is reciprocated one time, the drive source is controlled such that while one object is supplied, the eccentric cam is fully rotated a plurality of times. Alternatively, in the case where the pivotable cam has a plurality of projections on its cam surface and, when the cam is rotated by 360 degrees, the promoting member is reciprocated a plurality of times, the drive source may be controlled to rotate the cam by only an angle smaller than 360 degrees. According to the fifteenth feature (15), since the promoting member is reciprocating plural times while each one object is supplied, the present apparatus is more effectively prevented from failing to supply each object. As explained above in connection with the twelfth feature (12), the higher the frequency of movement of the discharging-promoting member is, the more chances the objects can enjoy to enter the chute, so that a plurality of objects may enter the chute while one object is supplied. After the chute is filled with the objects, no more objects can enter the chute even if the promoting member is moved. This, however, is not problematic. Thus, the present apparatus can more reliably supply the objects.
(16) According to a sixteenth feature of the present invention that includes any one of the first to fifteenth features (1) to (15), the arranging and supplying apparatus further comprises an object-supply portion from which the apparatus supplies the objects one by one, and a feeding device which feeds the objects arranged in the array in the chute, to the object-supply portion. Since the present apparatus employs the feeding device, the apparatus can reliably feed the objects arranged in the array in the chute, to the object-supply portion. However, it is possible to move the objects to the object-supply portion, without employing a feeding device. For example, the entirety of the chute is inclined and, owing to the inclination of the chute, the objects are moved from the hopper-side opening of the chute to the object-supply portion.
(17) According to a seventeenth feature of the present invention that includes the sixteenth feature (16), the feeding device comprises an air-flow producing device which generates, in the chute, an air flow in a direction from the hopper toward the object-supply portion.
(18) According to an eighteenth feature of the present invention that includes the seventeenth feature (17), the air-flow producing device comprises a negative-pressure producing device which is connected to the object-supply portion and which sucks an air in the chute and thereby generates the air flow in the direction from the hopper toward the object-supply portion so that the objects in the chute are fed toward the object-supply portion.
(19) According to a nineteenth feature of the present invention that includes the sixteenth feature (16), the feeding device comprises an endless annular belt and a belt drive device which circulates the belt, and the chute includes, in addition to the end portion thereof as a first end portion on a side of the hopper, a second end portion which is opposite to the first end portion and which opens in a vicinity of an upper surface of an upper portion of the endless belt. This feeding device can be called as a xe2x80x9cbelt-typexe2x80x9d feeding device and may be provided by the belt-type feeding device disclosed in Japanese Patent Application laid open upon Publication No. 11(1999)-20933 and corresponding to U.S. patent application No. 09/106,703 assigned to the assignee of the present application.
(20) According to a twentieth feature of the present invention that includes any one of the first to nineteenth features (1) to (19), each of the objects is an electric component which has a generally rectangular-parallelopiped shape. The present arranging and supplying apparatus may be employed in an EC feeder which supplies ECs. The EC feeder may be used for supplying ECs to an EC mounting device which mounts the ECs on a circuit board such as a printed-wiring board. However, the present apparatus may be employed in an EC feeder other than the EC feeder for supplying the ECs to the EC mounting device, for example, an EC feeder for supplying ECs to an EC transferring apparatus which holds and transfers ECs.